Here is some more feedback on the recent CarPlay integration.
I have used it for more than 20 hours of off grid navigation over the last couple weeks. I also intentionally hid my phone along with making sure that I did not have cell service in order to force myself to use it as it works through my Sony head unit. I have learned quite a bit about what works well and what it lacking.
1. It's very nice having one less screen in the vehicle
2. Getting routes, waypoints, and maps downloaded ahead is paramount to a good experience
3. Zooming in/out works well
4. I do not like that that vehicle marker stays in the center of the screen and you cannot move the map around. This comes in handy in order to see what is out in front of you and allows to see what is coming up. This is something I used often on the tablet I used to run and really the only thing I miss badly.
5. You cannot set waypoints or start recording a track from the head unit. This would be nice, but not real critical, at least in the way I use it.
6. It never crashed, or acted oddly, so I am pretty pleased with the CarPlay version.